Carpenter&#39;s square.



PATENTED AUG. '6. 1907 E. 0. IVERSEN.

' GARPENTBRS SQUARE.

APPLIOATION FILED Dm'zs, 190s.

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EINAR OLAS IVERSEN, OF CHICAGO, ILLINOIS.

CARPENTERS SQUARE.

Specification of Letters Patent.

Patented Aug. 6, 1907.

Application filed December 28,1906. Serial No. 349,849.

To all whom t may concern:

Be it known that I, EINAR OLAs IvERsEN, a citizen ol the United States, residing at Chicago, in the county ol' Cook and State oi Illinois, have invented certain new and uselul Improvements in Carpenters Squares, oi which the following is a specification.

My invention relates to tools and has special relerence to carpenters squares. Its chief objects are to provide a tool oi that class so constructed that it can be readily taken apart thus rendering it more portable and convenient lor carrying and permitting it to be placed in an ordinary box or bag.

Further objects of my improvement are to provide means for rendering the joints, which must necessarily enter into any separable construction, accurate and durable, and to furnish a connecting member of solid construction thus giving strength and firmness to the joint.

Further objects oi my invention are to provide a tongue and groove joint at the line of junction oi the blades in order to prevent lateral displacement which would tend to destroy the efficiency oi the tool; and to furnish means or securing the parts together when assembled in order to prevent accidental displacement.

I accomplish the above mentioned and other minor objects by the device illustrated in the accompanying drawing which forms a part oi this speeiiicatien and in which Figure I is a side view of my improved separable square with the parts assembled; Fig. 2 is a fragmentary view of the reverse side showing the retaining screws; Figs. 3 and 4 are iragmentary views enlarged oi the joint ends oi the blades, and Figs. 5 and G are enlarged sectional views oi Fig, l.

Referring to the drawing, '7 indicates the large blade and 8 the small blade of a carpenters square, These blades are each formed of a separate piece, the contiguous ends being cut on a bevel so that when joined they will iorm a true right angle, the line oi junction 9 eX- tending from the inner to the outer angle. The blades are firmly held in apposition by a connecting piece or union l0 which has two arms Il, l2, formed at right angles with each other. The larger oi the arms Il is received into a groove or gain I3 cut in one side of the large blade 7, the margins I4 being undercut, or dovetailed to correspond with the dovetailed edges I4 oi the said arm ll oi the union. The margins oi the smaller arm l2 are similarly dovetailed to engage a like groove l5 cut in the side oi the small blades 8. The ends I6 ol' the union are preferably rounded and the extremities el the gains I3, l5, are iormed to correspond, this shape giving a moreI accurate lit and being more easily manuiactured than when the ends are left square.

The gains are preicrably made oi a depth equal to about hali the gage oi the blades and the union loi-med ol a corresponding thickness so that the latter will be flush with the blade sui-laces.

As the blades of the square are proportionally very much longer than their width, the strain upon the dovetailed margins of the union will be correspondingly great, and there will be more or less tendency to give in a joint which is irictionally held against such a powerful leverage. I overcome the tendency to lateral displacement by iorming a tongue and groove joint where the inclined faces oi the blades come together to form the junction 9. The tongue I7 oi the joint is iormed on the joint iace oi the small blade and a corresponding groove I8 is provided in the opposing joint iace oi the large blade, although this order may be reversed without changing the result.

The blades are readily assembled by sliding the arms of the union l0 into their respective gains until the tongue I7 engages the groove I8 and the blades are in close apposition at the juncture 9.

v To prevent the blades rom working loose when subjected to hand usage by the slipping oi the union in its gains, I provide locking screws 19 which pass through the blades and engage threads in the arms of the union the holes for the screws in the blades being countersunk so that the heads are flush with the i'ace oi the tool.

Having thus described my invention what I claim as new and desire to secure by Letters Patent, isz- 1. A separable square including a plurality ol blades, a right-angled connecting member separable from said blades, and a tongue and groove beveled joint at the junction of the blades.

2. A, carpenters square including a plurality of separable blades, a right-angled connecting member separable from said blades, a tongue and groove beveled junction between the ends of the blades, and means for securing the parts when assembled.

S. A separable square including a plurality of detachable blades each blade provided with a lateral gain, a connecting member adapted to engage the said gain in each blade, a tongue and groove junction between said blades, and means for locking the blades in engagement with said connectingl member.

4. A square including a plurality of separable blades each blade provided with a lateral gain having undercut margins, a right angled union having dovetailed edges adapted to engage said lateral gains, a tongue formed in the end of one blade and adapted to engage a groove :formed in the other blade and means for locking the parts when assembled.

In testimony whereof l aliix my signature in presence of two witnesses.

EINAR oLAs Ivnnsnn.

Witnesses G. S. STAUGELA'UD, CHARLES B. OTT, 

